Method of recording sound



W./H. BRISTOL.

METHOD OF RECORDING SOUND.

APPLICATION 3 JAN. 13. 1920.

1,380,8 4 Patented June 7, 1921.

gwbmtoz an stares repeat WILLIAM H. BRISTOL, OF "WATERBURY, CONNECTICUT.

METHOD 'OF RECORDING SOUND.

Specification of Letters Patent.

atentecl June 7, I921.

Application filed January 13, 1920. Serial No. 351,146.

To all whom it may concern:

Be it known that I, WV LLIAM H. BRrsToL, a citizen of the United States,and a resident of Waterbury, in the county of New Haven and State ofConnecticut, have invented cer tain new and useful Improvements inMethods of Recording Sound, of which the following is a specification.

The invention relates to a method of and apparatus for effecting arecordof a vocal or instrumental selection with suitable accomthat it isdifficult to faithfully reproduce the different instruments. Pianoaccompaniments have been especially difficult to reproducesatisfactorily.

The present invention has for its object to effect a more natural recordof the music of an accompanying orchestra, piano, organ or the like; andparticulary to allow for'the recording of a greater number ofinstruments than has been heretofore practical. In carrying out theimproved method, I have found that with vocal selections perfectarticulation is maintained, the recording being effected in the usualmanner as transformations impair the reproduction, and that theinstrumental accompaniment is, furthermore, faithfully rendered and maybe had at the desired intensity. 'It will be appreciated, where both thesoundlwaves emanating from the instruments as well as those from thesoloist are to be collected by a horn or resonator apparatus common toboth, as generally carried out, that the instruments must be located ata limited distance from one portion of the horn and that an artist orartists must render the selection practically into the mouth of the saidhorn.

In accordance with the present inventlon,

the vocal or other selection is rendered substantially as heretofore bythe soloist in close proximity to the mouth of a horn,'but theinstruments are located at an appreciable distance from their collectinginstrumentality and from the artist or artists, who may be, preferably,also acoustically insulated therefrom. Moreover, the sound emanatingfrom the instruments is not received directly I by the mouth of a horn,but the combined sound waves therefrom are to be received by anelectrical transmitting instrument to affect same, the impulses thereofamplified,

and then directed to the recording apparatus. In this manner, noexcessive strain is put upon the transmitter member which need onlyfaintly transmit the sound waves, the

location being such that a not too strong action is produced thereonfrom the instruments, the transmitter for this purpose beingpreferablylocated at an appreciable distance therefrom, for example from 10 feetto 35 feetaway. This allows for the repro-.

duction of the renditions of a full symphony orchestra, as comparativelyweak impulses thus reproduced by the transmitter are properly amplifiedby a thermionic ampli fier of audio frequency, whereupon impulses ofsufficient intensity are provided and are caused to affect the recordingmechanism simultaneously with the impulses received through the hornfrom a song of a singer or from musical instruments to be accompanied.

A conductor may be so positioned as to view both the orchestra and thesoloist; and the individual instruments composing the orchestra are ofcourse to be arranged at distances best suited to the reproduction,being 9 so located, also, with reference to the transmitter as toprovide for the proper intensity of the transmitted impulses. The entirerecording maybe conducted in a room suitably constructed andacoustically arranged for that purpose and in which there may beprovided a partition or separating wall to acoustically insulate thesoloist as well as the'recording mechanism from the direct effect of theinstruments, thereby individualizing the selection. Thus, the recordingmechanism may be installed in a convenient location and preferably inmanner that both the soloist and the orchestra shall be visible to theconductor.

The accompanying drawing illustrates, diagrammatically, the generalarrangement and apparatus employed in carrying out the novel method ofeffecting a record of a selection with accompaniment.

As shown, the recording may be efi'ected in a room or a suitableinclosure 1 arranged to prevent the reflection of sound waves, thevarious instruments 2, constituting the orchestra or'the like, beingarranged in any suitable manner'for example as at the back of the roomwhile the position of the singer or's olois't 3 is removed some distancetherefrom and also acoustically insulated from the" said instruments. bymeans of a wall or partition 4.5 The recording apparatus 5, maybe ofany'of the well-known types and forms no-particular feature of thepresent invention, and is to be located in proximity to the soloist 3 sothat the horn 6 of said "apparatusnmay receive directly through itsmouth the sound waves emanating from the soloist'3'.'f

' The horn 6 is provided, however, with an .inletor second opening nearits inner end and through which sound waves, received in mannerhereinafter set forth, are combined withthose delivered into the mouthof the horn 6 to act simultaneously upon the recording portion of therecording apparatus 5. The sound waves' emanating from the orchestra 2are, therefore, notdinectly .delivered into the horn 6, as has /been thepractice heretofore, but are collected-by an electrical transmittingdevice 8, of any wellknown or special construction and the impulses setup thereby may be amplified by a suitable electrical amplifyingapparatus 9 of audio frequency, such as a one or more stage amplifier ofthe Audion typei From this amplifier, the impulses, properly magnified,are directedjto a receiver member 10 communicating with the inlet 7, thereceiver in turn delivering the sound. waves through said inlet 7' tothe horn 6 and the diaphragm of the recording apparatus-5. v i

Theconductor ll'may be located at any convenient point where he may viewboth the orchestra and soloist to suitably direct both. It will beunderstood, of course, that the various orchestral instruments 2 will bearranged in positions best suited to the reproduction desired, thetransmitter 9 being located at. a distance therefrom to aflord the bestresults'an'd provide the desired intensity, suit-able regulationbeingthereby provided for.

aeoeea jecting same to thermionic amplification of audio frequencysolely, and simultaneously recording both upon the record surface.

3. The method of efiecting upon a suitable record surface a.phonographic record of a selection with accompaniment, which consists inacoustically separating the selection from its accompamment, renderingthe former in immediate proximity of recording mechanism, and collectingelectrically the accompaniment.

4c. The method of effecting upon a suitable record surface, aphonographic record of a selection with accompaniment, which consists inacoustically separating the selection from its accompaniment, renderingthe former in immediate proximity to recording mechanism, collectingelectrically the accompaniment, electrically transmitting andthermionically amplifying same, and simultaneously recording both uponthe same record surface.

5. The method of effecting upon a suitable record surface, aphonographic record of a vocal selection with instrumentalaccompaniment, which consists in acoustically separating the vocalselection from its instrumental accompaniment, rendering the for-vmer'inimmediate proximity to recording mechanism, collectingtheaccompaniment and electrically transmitting same and under thermionicamplification, and simultaneously recording the two upon the same recordsurface.

Signed at 'aterbury in the county of New Haven and State of Connecticutthis 10th day of January A, D. 1920.

W'JULLTAM H. BRISTOL.

